NZ201835A

NZ201835A - Trailer suspension:stub axle offset from beam axle

Info

Publication number: NZ201835A
Application number: NZ201835A
Authority: NZ
Inventors: G D Malcolm
Original assignee: G D Malcolm
Priority date: 1982-09-07
Filing date: 1982-09-07
Publication date: 1985-02-28
Also published as: AU1873983A; CA1222532A; US4553774A; AU565657B2

Description

FORM 5.

■ NEW-ZEALAND S.9.

Reg 4 Fee: $80.00 Prk>nt-/ [ Cotttp&S? Cpe-i-Jficatson Filed: C\lzs: $k°.9.

Publication D.«te: P;0. Journal Wo: 2 8FEB1985 fp~b2 PATENTS ACT 195 3. 2-DIZ3S Insert number of Provisional Specification(s) (if any) and date(s) of fi ling; otherwise leave blank.

Number: 2018 35 Date: 7 September 1982 COMPLETE SPECIFICATION Hnsert Title of Invention.

Insert full name, full street address and nationality of (each) applicant.

VEHICLE SUSPENSION I/WE GEORGE DAVID MALCOLM, A New Zealand citizen of 1-10910 Bonaventure Drive, Calgary, Canada T2J 4Y9 hereby declare the invention for which I/we pray that a patent may be granted to me/us and the method by which it is to be performed, to be particularly described in and by the following statement- Indicate if following page is numbered '1(a)' 201835 This invention relates to a suspension, specifically designed for use on trailed vehicles, although it is possible to use it on other vehicles in some circumstances.

It has been common practice in the past to provide trailer suspensions in the form of a main or beam axle with a stub axle extending out from each end thereof along a line parallel to, but not collinear with, the main axle. The stub axles are typically mounted vertically above the main 10 axle and secured to it by a pair of end plates or a box section through which both axles pass. Alternatively, the main axle may itself be curved upwardly and then outwardly near each end. Adjacent the box section on the upwardly shaped portion a leaf spring is secured to the suspension to 15 enable a trailer body to be mounted upon the axle.

However, the construction at each side takes up a substantial amount of the width of the trailed vehicle, and it has not been possible 'to make full use of the space 20 between the wheels.

The object of the present invention is to provide an arrangement whereby the leaf springs are as close to the wheels as possible. • 10 The present invention consists in a suspension comprising a beam axle, a pair of spaced plates at each end of the beam axle through which said beam axle passes, a stub axle at each end of the beam axle each stub axle passing through a pair of said plates, the stub axles being offset from the beam axle and a leaf spring at each end of the beam axle fixed between the plates and between the stub axle and the beam axle.

A preferred form of the invention will be described by way of example with reference to the accompanying drawings in which: Figure 1 is an elevation of part of a trailer suspension, incorporating the present invention; Figure 2 is a plan view in direction II-II of Figure 1; and Figure 3 is an end view in direction III-III of Figure 1.

In its preferred form, as shown in the drawings, the present invention comprises a trailer suspension having a main or beam axle 1, typically in the form of a hollow box section 201835 as shown. At each end of the beam axle is a pair of parallel, spaced end plates 2, 3. The end plates are provided with a square hole to provide an interference fit onto the axle. The plates are forced onto the beam, using a welding is required).

The inner plate 3 is typically about 70 mm in from the end so that the spacing between the plates is about 65 mm. The 10 plates extend upwardly from each end of the beam axle and at each end a stub axle 4 extends through the upper end of the plates, being welded to both plates. The free end 5 of the stub axle extends outwardly from the end plates to a position where a wheel can be mounted on it. The inner end 15 6 of the stub axle coincides with the inner end plate 3.

The beam axle 1 may typically be 60 or 65 mm wide and the stub axles 4 typically 40 mm in diameter. The gap between the stub axle and the main axle is typically about 50 mm. 20 Passing through this gap is a leaf spring 9, typically comprising two or three leaves 10, with a load spreading spacer plate 11, typically about 6 mm in thickness, positioned above or below the leaf spring where it passes between the end plates 3, 4. hydraulic press and then welded to it (although only nominal zot835 The leaf spring is located upon the beam axle by means of a round bolt head 12 or other stud projecting from the spring. The bolt, passes through the spring leaves 10, spacer plate 11 and the head 12 through a locating hole provided in the top of the beam axle. Positioned upon the leaf spring is a pair of opposed wedges 14, 15 typically cast in malleable iron. The first wedge 14 is slightly forward and the second wedge 15 slightly rearward of the stub axle. Both wedges taper inwardly towards a point immediately beneath the axis of the stub axle. The stub axle 4 coacts with the tapered upper surfaces 16 of the wedges. The wedges are secured together by means of a bolt or preferably a pair of parallel bolts 19. As the nuts 20 on each of these bolts are tightened the wedges are urged towards each other, to become forced between the leaf spring 9 and the stub axle 4. The spring is thus firmly held in the space between the two axle components. By this means, the axle assembly is prevented from moving relatively to the leaf springs.

The stub axle is provided with a pair of grooves 20, typically about 5 mm in radius, to facilitate assembly of the bolts 19 through the wedges.

This construction provides a simple and effective means of making the most of the space between the stub axle and the r 10 beam axle. The leaf spring, by passing between the end plates connecting the stub axle to the beam axle, does not take up space between the wheels which it would otherwise do, thus allowing a wider main body to lie in the space between the stub axles.

Because the wheel centre is close to the spring centre, bending moments are lower than is usual with prior art suspension assemblies facilitating the use of lightweight materials.

Various modifications to the above can be made without departing from the scope of the present invention as claimed.

Claims

') n i o c I o j 5 WHAT I CLAIM IS

1. A suspension comprising a beam axle, a pair of spaced plates at each end of the beam axle through which said beam 5 axle passes, a stub axle at each end of the beam axle each stub axle passing through a pair of said plates, the stub axles being offset from the beam axle and a leaf spring at each end of the beam axle fixed between the plates and between the stub axle and the beam axle. 10

2. A suspension as claimed in claim 1 which includes at each end a pair of opposed wedge members located between the leaf spring and a said axle. 15

3. A suspension as claimed in claim 2 wherein the wedge members are fixed together by means of a bolt passing through them.

4. A suspension as claimed in any one of claims 1, 2 or 3 20 wherein a spacer plate lies between the leaf spring and the beam axle.

5. A suspension as claimed in any one of the preceding claims wherein the leaf spring is .located on the beam axle 25 by means of a stud projecting from the spring engaging with a hole in the beam axle.

6. A suspension comprising a beam axle, a pair of spaced plates at each end of the beam axle through which said beam stub axle passing through a pair of said plates, the stub axles being offset from the beam axle and a leaf spring at each end of the beam axle fixed between the plates and between the stub axle and the beam axle by a pair of opposed 10 wedge members being fixed together by means of a bolt passing through them, said leaf spring being located on the beam axle by means of a stud projecting from the spring engaging with a hole in the beam axle. 15

7. A suspension substantially as herein described with reference to the accompanying drawings. 5 axle .passes, a stub axle at each end of the beam axle each 20 25 -8- J rb7 HARDIE & CCX Patent Attorneys for the Applicants). .